Changeable exhibitor



c. F. MALMBERG 1,971,455

CHANGEABLE EXHIBITOR Filed March 6, 1933 2 Sheets-Sheet 1 Aug. 28, 1934.

Aug. 28, 1934.

c. F. MALMBERG CHANGEABLE EXHIBITOR Filed March 6, 193;

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m WFE... ,I M .w wwiiiiwyg mm E\%NMN 0 sq Patented Aug. 28, 1934 UNITED STATES 1,971,455 V CHANGEABLE EXHIBITOR Constantine F. Malmberg, Normal, Ill. Application March 6, 1933, Serial No. 659,885

15 Claims.

This invention relates to changeable exhibitors of the kind in which a series of cards or like display units are positioned successively for View through a window or' opening, and more particularly to exhibitors of this class which are especially adapted for educational purposes.

In the teaching, especially of small children, an instructor sometimes desires to find out how quickly the pupils recognize pictures or read v printed words placed before them. Thus a teacher may hold printed cards up for a short time for the class to view in order that the rapidity with which the pupils are able to recognize the picture or read the printed matter may beascertained. Naturally the period of exposure of the cards varies with such factors as the age of the pupils and the nature of the matter displayed, and heretofore it hasbeen possible for the teacher to control the exposure time more or less by guesswork and only approximately. Of course, in order that a definite indication of the alertness of the pupils be obtained it is necessary that the time of exposure be controlled accurately and be variable readily in accordance with the age of the pupils or the nature of the matter displayed.

An object of the present invention is to provide achangeable exhibitor adapted to display successively a plurality of cards or the like each for a selected definite predetermined time intervalpthe arrangement being such that any one of several definite display time interval sequences may be employed.

Another object is to provide a changeable exhibitor adapted to be turned in a horizontal plane so as to position eitherof two opposite display openingsfor view from a given direction.

A further object is to provide a movable door or panel. device positioned in front of a selected part of the display opening of an exhibitor of the kind described so as to obscure from view a portion of a display'card orthe like positioned behind the opening.

i A further object is to provideimproved mechal5 nism for feeding a plurality ofdisplay cards or the like to position them successively for View.

enlarged scale a swivel mount and detent de vice;

Figure 4 is a view showing card feeding and associated mechanism in side elevation and a mechanism housing in longitudinal vertical 9 section, the section being taken on the line 44 of Figure 1;

Figure 5 is a transverse vertical sectional view taken on the line 55 of Figure 4;

Figure 6 is a detail view in side elevation and on an enlarged scale of a track and lifting arm;

Figure 7 is a detail view in top plan and on an enlarged scale of the track and lifting arm;

Figure 8 is a fragmentary horizontal sectional view taken on the line 8-8 of Figure 4, and drawn on an enlarged scale; 7

Figure 9 is a detail view of a card carrier and card drawn on an enlarged scale.

Figure 10 is a detail view in front elevation of a panelled door, drawn on an enlarged scale; and Figure 11 is a fragmentary horizontal view taken on the line 1111 of Figure 4.

A preferred embodiment of my invention is illustrated in the accompanying drawings as including a base and cabinet A and an exhibitor proper B supported on the cabinet for turning movements in a horizontal plane by means of a swivel mount generally designated 1. The cabinet A serves both to support the display apparatus and to provide storage space for extra dis-. play cards or other material, and preferably is provided with doors 2. i

The exhibitor proper B includes a housing generally designated 3 and comprising a base or bottom 4, end walls 5 and 6, side walls '7, and a top 8. The end walls 5 and 6 are provided with display windows or openings 9 and 10 respectively, the arrangement being such that display material may be exhibited through either opening 9 or 10 by turning the housing 3 on the swivel mount 1 so as to bring the end wall 5 or the end wall 6 intoview. Strictly speaking, either the wall 5 or the wall 6 may at times be the frontwalL'but for the purposes of description the wall 5 will be termed the front wall and the wall 6 the rear walll 1 The swivel mount 1 includes a combined vertical bearing and horizontal thrust plate 11 secured to the top of the cabinet A,; and a shouldered pintle 1'2 fitting in the bearing and being provided with a plate .13 secured to the bottom or the casing 3. This mount servesto support the casing 3 and to permit its readily being swung in a horizontal plane to present either the front or rear of the casing for view. In order to assist in bringing the casing to rest in a position with either the front or rear wall disposed for view, a pair of vertically extending spaced pins 14-14 is connected to the thrust plate 11, and a pair of similar pins l5-15 is connected to the plate on the opposite side of the pintle 12. Spring catches or detents 1617 formed with loop portions 161'7 adapted to fit between the pins 14 and 15 are secured to the pintle 12. When the pintle is in the position shown in Figure 3 and it is desired to rotate the housing 3 to present the opposite end thereof for view, slight pressure on the housing will overcome the holding action of the detents 17, causing the latter to be freed from engagement with the pins 14 and 15. When the casing has been rotated through one hundred and eighty degrees, the detent loop portions 17 will enter the spaces between the pins, thereby automatically bringing the casing to rest in the desired position.

Mounted within the casing 3 and on the bottom 4 thereof are four standards 18 upon which are supported a pair of spaced upper channels 19 extending longitudinally of the casing and a pair of spaced lower channels 26 disposed respectively directly under channels 19. lhe channels 19 provide upper track upon which is carried a plurality of card carriers 21, each carrier comprising a rod 22 extending transversely of the casing between the channels 19 and being fitted at its opposite end with rollers 23 engaging the channels. Secured to each carrier rod is a spring clip 24 adapted to clamp releasably a display card 25. As shown in Figure 4, the upper track (channels 19) serves to hold a series of cards hanging in vertical position, and the bottom track (channels 29) serves to hold a similar series of cards. The height of the top track is such as to position the cards hanging therefrom substantially at the level of the openings 9 and 10 in the front and rear walls, so that the end cards are visible through the openings, but the cards supported on the lower track are not visible from outside the casing.

In order to enable the obscuring from view of a selected part of card positioned in front of either opening 9 or ii), I have provided a door frame 26 including channelled top and bottom uides 27 in which are mounted sliding panels 28 and 29, the door frame being provided with eyehangers 30 adapted to be connected to hooks 31 on the front wall 5 or to hooks 32 on the rear wall 6 so as to position the door frame and panels in front of either opening 9 or 11). Referring to Figure 1, it will be noted that the panel 29 is in its inner position, obscuring from View the right i and which pupils are able to read only a portion of the same phrase or sentence within a given time interval. 4 It will be understood that the carriers and cards are moved along the trac {S transferred from one to the other at fixed intervals of time so as to display each card for a uniform selected time. In order that the feeding of the cards along the tracks be uniform, it is desirable that there be enough carriers to extend along the entire length of each track; and to prevent carriers i from running off the ends of the tracks the latter are formed with depressions 33 and 34 at the front and rear of the top channels 19 and depressions 35 and 36 at the front and rcar ends of the bottom channels 20.

Vertically disposed plates 37 are mounted between the upper and lower tracks on both sides of the mechanism, these plates being provided at their front ends with curved guide surfaces 38 and at their rear ends with similarly curved guide surfaces 39. These surfaces serve to guide carriers being lifted from the rear end of the bottom track to the rear end of the top track and to guide carriers being lowered from the front end of the top track to the front end of the bottom track, as will be described more particularly hereinafter.

On each side of the machine there is a lifting arm generally designated 40 and including a tubular part 41 pivoted as at 42 to the plate 37 on that side of the machine and a rod extension 43 which fits adjustably within the tubular part- 41 and is held in adjusted position by means of a set screw 44. The outer end of the extension 43 is bent inwardly as at 45 (see Figure 7) so as to extend behind the tracks, the extreme end portion of the rod being return-bent at 46 towards the track and formed with a curved card carrier seat 47 adapted to receive and support a carrier as the latter is moved rearwardly off the track channels 20. A similar arm 48 is provided for lowering carriers from the front end of the top channel 19 to the front end of the bottom channels 20, this lowering arm also including a tubular portion 49 pivoted at 50 to the plate 37 and a rod extension 51 fitting adjustably in the tubular part 49 and being held in adjusted position by means of a set screw 52. The end of the extension 51 is formed similarly to that of the extension 43 on the lifting arm 49, so as to provide a card carrier seat 53 adapted to receive a car- 01 set,

fecting simultaneous movement of the arms 40 and 48 to upper and lower positions.

In operation, when the cards are to be shifted to present a new one for view, the rear-most carrier on the bottom channels is pushed beyond the channels onto the seat 47 of the lifting arm 40, after which the arm is swung upwardly to move the carrier into the plane of and behind the top channels 19, after which the arm returns to its lower position. For retaining the carrier, which has been moved into the plane of the top channels, I provide on each side of the machine a detent 56 pivoted as at 5'7 to the plate 37, the detent being urged to its Figure 4 position by means of a spring 58 interposed between an arm 59 on the detent and the adjacent A being moved upwardly, it engages the rear edge lull of the detent and moves the latter inwardly to permit passage of the carrier upwardly. When the carrier has been moved past the detent, the latter will return to its Figure 4 position wherein its upper end will be disposed under the carrier for supporting the latter and holding it in the plane of the channels 19 when the arm 40 returns to its lower position. The outer ends of the lifting arm extensions 43 move in an are spaced from and concentric with the curved guide surfaces 39,

so that the carrier is prevented from falling off the seats 47 of the lifting arms. 1 It will be understood that during each feedin movement, in addition to transferring a carrier from the rear of the bottom channels to the rear.

upper arm of a bell crank lever .66, the other arm 67 of which is connected to operating mech anism in a manner to be described later. The outer or rear end of each feeder bar 62 extends inwardly as at 68 and downwardly as at 69 behind the rearmost carrier on the upper channels.

For feeding the carriers on the lower channels rearwardly, I provide a bottom feeder bar or lever 70 pivoted as at 71 on a bracket 72 secured to the bottom 4 of the exhibitor housing. The lever is normally held in its Figure 4 position by means of a spring 73 interposed between the lever and the adjacent bracket 18, and a stop lug 74 on the lever is adapted to engage a lug 75 on the bracket '72 for limiting movement of the lever under the urge of the spring '73.

Actuating mechanism is provided for operating thetransfer arms 40 and 48, the top feeder bars 62, and the bottom feeder bar '70 in timed relation so as first to raise the rearmost carrier from the bottom channels 20, then to feed the carriers on the top channels forwardly and to move the leading carrier on the top channels onto the seat 53 of the arm 48, then to deposit the carrier being raised upon. the top surfaces of the detents 56, then to lower the carrier just moved onto the seat 53 of the arm 48 to a position in front of the forward ends of the bottom channels, and then to swing the bottom feeder bar 70 in order to feed the carriers on the bottom channels rearwardly. The mechanism shown by way of example includes a driving motor 77 mounted on a bracket '78 and having its shaft provided with a worm wheel '79 in engagement with a worm gear 80 secured to a shaft 81 mounted for rotation in bearing brackets 82 and 83. A drum 84 mounted on the shaft is constrained to rotate therewith by means of a key 85 on the shaft extending through a keyway in the drum, the arrangement being suchas to permit shifting of the drum axially of the shaft. Adjacent the left hand end of the drum (as viewed in Figure 5) is a series of eight circumferentially spaced projections 86 86 86 etc. Spaced axially towards the right of the projections 86 etc. is a second series of projections 87, there being fewer projections, in this series than in the first series, and toward the right of the projections 87 are twoother series of circumferentially spaced projections 88 and 89 respectively, each series comprising a different number of projections. When the drum is in the position shown in Figure 5,- the projections 86 86 etc. ofthe series first mentioned lie in the same plane as a pawl 90 fixed to a transversely extending shaft 91 journalled in brackets 92, the nose of the pawl being disposed for engagement by the projections 86 etc. and the other end of the pawl being pivoted to a vertically extending operating rod 93 which passes through and beyond a block 94 pivotally connected to the segment 54 of the lifting arm 40 on one side of the machine, the rod 93 being fitted for sliding movements in the block 94. The upper end of the rod passes loosely through the arm 67 of the bell crank lever 66. A spring 95 is inter posed between the block 93 and a collar 96 fixed to therod 93, and a spring 97 surrounding the rod rests upon the top of the arm 67. A nut 98v is secured to the top end of the rod 93 and nor mally is spaced above the upper end of the spring 97. At the end of the shaft 91 opposite that to which the pawl 90 is secured is mounted a lever 90 pivotally connected to an'operating rod 93 which passes through a block 94"pivotally mounted in the lifting arm 40 at that side of the machine. The rod 93 extends through the arm 67' of the bell crank lever 66 a spring 95 being interposed between the block 94 and a collar 96', and a spring 97 being mounted on the rod 93' between the arm 6'7 and a nut 98 normally spaced above the upper end of the spring 97. By means of the connecting shaft 91 the operating rods 93 and 93 and associated parts are adapted to be operated in unison. A pawl 99 pivotally mounted as at 100 on a bracket 101 is adapted to have its nose end disposed for engagement by one of the series of projections on the drum 84, the other end of the pawl being pivotally connected at 102 to a link 103 in turn pivotally connected at 104 to the feeder bar 70.

In order that the operation of the apparatus may be clearly understood, a complete cycle of operation will be described briefly. Assuming that the parts are in the positions shown in Figures 4 and 5, and that the motor 7'7 is running in a direction to drive the gear 80 and drum 84 in the direction of the arrow shown in Figure 4, there will be nomovement' of the card transferring and feeding mechanism until the projection 86 on the drum engages the nose of the pawl 90. When the projection engages the pawl it will rock the latter in a counter clockwise direction so as to move the operating rod 93 downwardly and also to move the operating rod 93 downwardly through the medium of the connecting shaft 93. and the crank 99. As soon as the operating rods 93 and 93 begin to move downwardly, the transfer arms l0 and 48 will start to swing upwardly, the seats 47 on the transfer'arms 40 carrying upwardly the carrier shown just back of the bottom channels 20. Because of the lost motion connection between the nuts 98 and 98 on the rods 93 and 93 and the springs 97 and 97' respectively, there will be no movement of thetop feeder bars 62 during the initial upward movement of the transfer arms. When the trans" fer arms have moved upwardly to approximately horizontal positions, the nuts 98 and 98' will engage the springs. 97 and 97, and through the latter will rock the bell crank levers 66 in a counter clockwise direction so as to move the top feeder bars 62 toward the left as viewed in Figure 4, thereby moving all of the carriers on the top channels 19 forwardly. This will provide a vacant space at the rear ends of the channels 19 for accommodating the carrier being raised, and at the same time will push the leading carrier on the top channels ofi the end of the latter onto the seats 53 of the lowering arms 48. During the latter part of the upward movement of the lifting the: spring 5.8- will: return the detent to its Figure 4 position wherein it will underlie the carrier just .moved upwardly by the lifting arms 40. After-the projection 86 moves past the nose of the pawl 90,.tl1e weight of. the transfer arms will cause: the latter to swing downwardly, returning to: their. Figure 4. positions, thereby, positioning theicarrier which has just previously been moved off the leading end of the top channels directly in; front of the leading ends of the-bottom channels; Soon after-"the parts have reached this position, the projection 86 will engage the nose of the. pawl.- 99, thereby rocking thelatter in a counter clockwise direction and swinging the bottom feeder bar toward thev right, duringwhich movement it will engage the carrier on the seats 53st the lowering armsv 48 and move all the carriers on the bottom tracks toward the right, forcing the rearmost carrier onto the seats 47 of the liftingarms 40, thereby completing the cycle. During continued operation of the motor 77, this cycle will be started over again when the projection 86 engages the nose of the pawl 90, the sequence of operation for each cycle being the .Isam-e as that described above.

It will be understood from the foregoing that, by employing a constant speed motor, the period during which each card is presented for view through the windows 9 or'lO will be constant. As

gpreviouslystated, it sometimes may be desirable 1 as to bring any one of the four series of projections into cooperative relation with the pawl 90. Thus, if it is desired to expose each card fora longer time, the drum may be shifted to position the series of projections 87 in the plane of the pawl, and since there are fewer projections 87 than there are projections in the first series m --86 etc. there will be fewer changes. of the cards during a given time, and consequently a longer exposure of each card.

A further feature of the invention resides in the provision of means for shifting the drum to position any one of the series of projections thereon in cooperative relation with the pawl 90. In the form shown, there is provided an extenjSlOIl sleeve 105 on the drum 84 provided with atoothed wheel 109 in mesh with the ribs 106 on the sleeve. A knurled operating disc 110 is fixed to the outer end of the shaft. It is apparent that by rotating the shaft 107 and the gear 109 the sleeve 105 and hence the drum 84; will be shifted axially of the shaft 81, thereby enabling any selected series of projections to be positioned in operativerelation to thepawl 90. A set screw 111 mounted in an extension 112 on, the bracket 108is adapted to engage the toothed wheel 109 for holding the latter and. the sleeve and drum in adjusted-position. It will be noted that, although the toothed wheel 109 is in constant engagement gardless of their positions to the shaft.

Although'the form of apparatus shown and de-- axially with respect scribed herein is believed to be a practical and the at present preferred embodiment of the invention, it will be understood that various changes may be made in the construction and relative arrangement of the parts without departing from the invention as defined in the claims.

I claim:

1. In a changeable exhibitor the combination of a housing having a display opening; means within the housing for positioning display matter in registry with said opening; and separate panels mounted for independent sliding movement in front of said opening and inwardly from the respective sides thereof whereby a selected part of display material behind the opening may be obscured from view and the remaining part presented to view.

2. In a changeable exhibitor the combination of a. housing having front and rear display openings; means withinv the housing for positioning display matter in registry with each opening; a door frame; means for removably mounting said frame in front of either opening; and separate panels mounted for sliding movement in said frame from the middle thereof laterally in both' directions respectively. a

3. In a changeable: exhibitor, the combination of spaced upper and lower tracks each adapted to support a plurality of carriers; a pivoted lift-' ing arm for transferring carriers from one end of the lower trackto the above end of the upper track; a pivoted lowering arm for transferring carriers from the opposite end of said upper track to the below end of said lower track; and means for operating said arms in timed relation.

a 4. In a changeable exhibitor, the combination of spacedupper and lower tracks each adapted to support a plurality of carriers; a lifting arm for transferring carriers from one end of the lower track to the above end of the upper track; a lowering arm for transferring carriers from the opposite end of said upper track to the below end of said lower track; a. feeder element engageable with av carrier on said upper track for moving the carriers thereon longitudinally of the track; and means for operating said transfer arms and said feeder element in timed relation;

5'. In a changeable exhibitor, the combination of spaced upper and lower tracks each adapted to support a plurality of carriers; a lifting arm for transferring carriers from one end of the lower track to the above end of the upper track; aloweringarm'for transferring carriers from the opposite end of said upper track to the below end of said lower track; a top feeder element engageable with'the 'endinost carrleratone end of said upper track for moving the carriers thereon longitudinally of the tracks in one direction; a bottom feeder element engageable with the endmost carrier on the lower track at the opposite end of the tracks for moving the carriers on the lower track longitudinally thereof in the opposite direction; and means for operating said transfer arms and said feeder elements in timed relation.

6. In a changeable exhibitor, the combination of spaced upper and lower tracks each adapted to support a plurality of carriers; a lifting arm for transferring carriers from one end of the lower track to the above end of the upper track; a detent having a part adapted when in nor mally' projected position toform a continuation of said upper track at said end thereof and being displaceable by engagement of a carrier being lifted forpermittingpassage of said carrier past the detent; and means for operating said lifting arm.

7. In a changeable exhibitor, the combination of spaced upper and lower tracks each adapted to support a plurality of carriers; a lifting arm for transferring carriers from one end of the lower track to the above end of the upper track; a lowering arm for transferring carriers from the opposite end of said upper track to the below end of said lower track; means connecting said arms for simultaneous movements; a feeder element engageable with a carrier on said upper track for moving the carriers thereon longitudinally of the track; an operating member connected to said lifting and lowering arms for operating them together; and a lost motion connection between said operating member and said feeder element.

8. In a changeable exhibitor, the combination of spaced upper and lower tracks each adapted to support a plurality of carriers; a pivoted lifting arm for transferring carriers from one end of the lower track to the above end of the upper track; a pivoted lowering arm for transferring carriers from the opposite end of said upper track to the below end of said lower track; intermeshing gears connected respectively to said arms whereby they are operable together; and means connected to one of said gears for operating the arms.

9. In a changeable exhibitor, the combination of spaced upper and lower tracks each adapted to support a plurality of carriers; a pivoted lifting arm for transferring carriers from one end of the lower track to the above end of the upper track; a pivoted lowering arm for transferring carriers from the opposite end of said upper track to the below end of said lower track; intermeshing gears connected respectively to said arms whereby they are operable together; a feeder element engageable with a carrier on said upper track for moving the carriers thereon longitudinally of the track; an operating rod pivotally connected to one of said gears; and a lost motion connection between said rod and said feeder element.

10. In a changeable exhibitor, the combination of spaced upper and lower tracks each adapted to support a plurality of carriers; means providing a curved guide surface extending between said tracks at one end thereof; a pivotally mounted transfer armhaving at its end a card carrier seat adapted to swing in an arcuate path adjacent said guide surface, said seat being formed with an open loop portion travelling in an arc spaced from and concentric with said curved guide surface.

11. In a changeable exhibitor, the combination of means for supporting a series of display units; a feeder element for advancing said units in stepby-step movements; a driving motor; and selectively variable feed time interval transmission mechanism interposed between said motor and said feeder element.

12. In a changeable exhibitor, the combination of means for supporting a series of display units; a feeder element for advancing said units in step-by-step movements; at driving motor; a rotatably mounted member operatively connected to said motor; a plurality of spaced series of spaced projections on said member, the respective series comprising different numbers of projections; a device connected to said feeder element and being adapted to be disposed for engagement by the projections of any selected series; and means for changing the relative positions of said device and said rotatable member to bring said device and the desired series of projections into cooperative relation.

13. In a changeable exhibitor, the combination of means for supporting a series of display units; a feeder element for advancing said units in step-by-step movements; a driving motor; a rotatably mounted drum operatively connected to said motor; a plurality of axially spaced series of circumferentially spaced projections on said drum; a device connected to said feeder element and being adapted to be disposed for engagement by the projections of any selected series; and means for shifting said drum axially to bring the desired series of projections into cooperative relation with said device.

14. In a changeable exhibitor, the combination of means for supporting a series of display units; a feeder element for advancing said units in stepby-step movements; a driving motor; a rotatably mounted shaft operatively connected to said motor; a drum on said shaft; a key and keyway constraining said drum to rotate with said shaft but permitting the drum to move axially of the shaft; a plurality of axially spaced series of circumferentially spaced projections on said drum; a device connected to said feeder element and being adapted to be disposed for engagement by the projections of any selected series; a plurality of circular ribs connected to said drum and spaced axially thereof; and a toothed adjusting wheel mounted with its axis transverse of the drum axis and having its teeth in engagement with said ribs.

15. In a changeable exhibitor, the combination of spaced upper and lower tracks each adapted to support a plurality of carriers; a lifting arm for transferring carriers from one end of the lower track to the above end of the upper track; a lowering arm for transferring carriers from the opposite end of said upper track to the below end of said lower track; a feeder element for advancing the carriers on one track in step-by-step movements; a driving motor; a rotatably mounted drum operatively connected to said motor; a plurality of axially spaced series of circumferentially spaced projections on said drum; pawls connected to said feeder element and said arms respectively and being adapted to be disposed for engagement by the projections of any selected series; and means for shifting said drum axially to bring the desired series of projections into cooperative relation with said pawls.

CONSTANTINE F. MALMBERG. 

